Feb. 4, 2009 -- An ancient killer is hiding in the remote forests of Siberia. Walled off from western eyes during the Soviet era and forgotten among the endless expanse of wilderness, scientists are starting to uncover the remnants of a supervolcano that rained Hell on Earth 250 million years ago and killed 90 percent of all life.

Researchers have known about the volcano -- the Siberian Traps, for years. And they've speculated that the volcanic rocks, which cover an area about the size of Alaska, played a role in runaway global warming that led to the end -- Permian mass extinction, the worst dying the planet has ever seen.

Now a team of researchers led by Henrik Svenson of the University of Oslo in Norway have performed a series of experiments, showing the volcano employed an arsenal of deadly weapons during its 200,000-year-long assault on the biosphere.

Prime among them was carbon. Searing magmas from the volcano intruded into the Tunguska Basin in eastern Siberia, a region laden with thick deposits of coal, oil and gas. Heat from the molten rock baked the hydrocarbons, turning the area into the world's largest fossil fuel-burning plant. In all, the volcano may have belched as much as 100,000 gigatons of carbon into the air (all of humanity emits about eight gigatons of carbon annually).

That's more than enough to cause a global climate apocalypse. But the team also wanted to know what happened when lava infiltrated the area's abundant salt deposits. When heated in a laboratory to 275 degrees Centigrade (527 degrees Fahrenheit), the salts released a host of toxic gases, chief among them methyl chloride, an efficient ozone-killer.

"This is the first geologically realistic evidence that ozone collapse during the end-Permian could have actually happened," Svenson said.

But there is still a lot of uncertainty surrounding the findings, Linda Elkins-Tanton of the Massachusetts Institute of Technology said.

"There is evidence of a large number of genetic mutations in the fossil record around this time," she said, which could be the result of an onslaught of ultraviolet radiation due to a weak ozone layer. "But the idea of ozone destroyers is pretty new. The question is whether or not the eruptions were powerful enough to inject gases into the stratosphere."

The answer may come from close examination of hundreds of pipe-like structures strewn throughout the Tunguska Basin. Often 300 meters (984 feet) in diameter, Svenson's team believes the pipes are ancient volcanic craters left over after the lethal mix of carbon and chlorine gases exploded into the atmosphere.

Now a team of researchers led by Henrik Svenson of the University of Oslo in Norway have performed a series of experiments, showing the volcano employed an arsenal of deadly weapons during its 200,000-year-long assault on the biosphere.

Prime among them was carbon. Searing magmas from the volcano intruded into the Tunguska Basin in eastern Siberia, a region laden with thick deposits of coal, oil and gas. Heat from the molten rock baked the hydrocarbons, turning the area into the world's largest fossil fuel-burning plant. In all, the volcano may have belched as much as 100,000 gigatons of carbon into the air (all of humanity emits about eight gigatons of carbon annually).

So 100,000 gigatons in a 200,000-year-long assault comes to .5 gigatons/year this is a joke right? Not near enough carbon to do any harm.

“This period marks the end of pivotal evolutionary development in marine life and the opening of the transition period leading to the subsequent ages of land animals.”

“This age was one of great life impoverishment. Thousands of marine species perished, and life was hardly yet established on land. This was a time of biologic tribulation, the age when life nearly vanished from the face of the earth and from the depths of the oceans. Toward the close of the long marine-life era there were more than one hundred thousand species of living things on earth. At the close of this period of transition less than five hundred had survived.”

“The peculiarities of this new period were not due so much to the cooling of the earth’s crust or to the long absence of volcanic action as to an unusual combination of commonplace and pre-existing influences—restrictions of the seas and increasing elevation of enormous land masses. The mild marine climate of former times was disappearing, and the harsher continental type of weather was fast developing...”

“Land was rising all over the world as the ocean beds were sinking...”

“Two new climatic factors appeared—glaciation and aridity. Many of the earth’s higher regions had become arid and barren...”

“Gradually the inland lakes and seas were drying up all over the world. Isolated mountain and regional glaciers began to appear...”

“Throughout these times of climatic change, great variations also occurred in the land plants. The seed plants first appeared... The insects underwent a radical change. The resting stages evolved to meet the demands of suspended animation during winter and drought...”

“The gradual cooling of the ocean waters contributed much to the destruction of oceanic life...”

No, I think I was saying the .5 GT/yr wasn't and couldn't have been the problem. As to what other noxious stuff came from the Siberian volcanism I will not comment. But if we're now doing 8 GT/yr and the earth temperatures are going down ....

The atmospheric effects of a supervolcano would not have been spread out evenly over a prolonged period. There would have been episodes of intensity followed by quieter periods. Furthermore, we have not proved there was not a monster boloid component that might have triggered the production of the Siberian Trappes, and torn the atmosphere apart.

I have long been of the opinion that the atmospheric disturbance of the KT meteor strike(s) destroyed the ozone layer. I see this as the explanation as to why birds (feather protected), small mammals (fur and nocturnal), alligators (hid under mud banks), and the like were able to survive.

Two books of interest are: When Life Nearly Died: The Greatest Mass Extinction of all Time, Michael J. Benton, 2003 and The Great Dying, Kenneth J. Hsu, 1986. Hsu, of course, wrote before the meteor explanation for the death of the dinosaurs 65 million years ago had been accepted.

That amount of CO2 could be easily absorbed by the biosphere over that period of time. The bolide component is interesting but a smoking gun has yet to be found.

Now the K-T event is a different story. We have the crater and other evidence that is pretty incontrovertible. At pretty much the same time there was a massive volcanic event that produced the Deccan Traps. This volcanism may have been caused or exacerbated by the impact.

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